Winston is only logging .info errors and doesn't log error to file or mongodb

I am using express-mongoose for my backend and winston as my logger. The problem is that winston is only logging the info messages not errors The logs in server.log

Error messages only get logged on console but neither in the file nor mongodb

the logger code

const { createLogger, format, transports } = require('winston');

// Import mongodb
require('winston-mongodb');

module.exports = createLogger({

transports:[
//Console transport
    new transports.Console(),

// File transport
    new transports.File({
    filename: 'logs/server.log',
    format:format.combine(
        format.timestamp({format: 'MMM-DD-YYYY HH:mm:ss'}),
        format.align(),
        format.printf(info => `${info.level}: ${[info.timestamp]}: ${info.message}`),
    )}),

// MongoDB transport
    new transports.MongoDB({
        level: 'error',
        //mongo database connection link
        db : 'mongodb://localhost/logs',
        options: {
            useUnifiedTopology: true
        },
        // A collection to save json formatted logs
        collection: 'edushare_logs',
        format: format.combine(
        format.timestamp(),
        // Convert logs to a json format
        format.json())
    })]
});

I created an error by not defining the jwt. the code

const logger = require("./utils/logger")
if (!config.get("jwtPrivateKey")){
    logger.error("FATAL ERROR!! JWT is not defined!")
    process.exit(1)
}

from Winston is only logging .info errors and doesn't log error to file or mongodb